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Guitar tube amp question?

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  • Guitar tube amp question?

    My amp pops when I switch out of standby. Apparently this is a common issue so I looked it up and learned that it is not a switch to mute with or save tubes when taking a break. Oops! Anyway what I have come to understand is that it protects the caps from inrush current. Is this really important on modern tube amps? According to this it looks like a lot of companies add this feature because people expect there to be one. Will it hurt to not even use the standby? I expect power supply caps are a bit better than they use to be. The amp is a peavey ultra (not ultra +). I think it is early 80s

  • #2
    A correctly implemented standby switch serves a very simple purpose: it turns off the B+ voltage to the tubes to mute the amp while you're on a set break. You could accomplish the same thing by turning down the volume pot, but players tend to want settings to be left alone once they get them where they want them. Turning off only the B+ instead of the overall power switch allows you to turn the standby switch back on when you're ready to play again and not have to wait for the tube heaters to warm up. Fender put the standby switch after the rectifier(s) and filter caps, so the filter caps were always charged and not subjected to inrush current every time the switch was employed. One can argue whether it was an unnecessary frill, but Leo Fender was a dyed in the wool cheapskate who never spent a buck on anything he thought he could get by without.